Symbol to use for Padding: AlignWithSymbol
The AlignWithSymbol Padding choice forces all imported stocks to have the same set of bar dates as the PadAlignSym stock by adding missing bars and removing extra bars.
This alignment is performed only within the existing date range of each stock. Extra bars are not added before the start or after the end of its data.
Since this setting is always simply one symbol, it should not be preceded by a $ as is normally done to reference a symbol within a formula.